This application is based on and incorporates herein by reference Japanese Patent Application No. 2000-304926 filed on Oct. 4, 2000, and Japanese Patent Application No. 2001-227199 filed on Jul. 27, 2001.
1. Field of the Invention
The present invention relates to a solenoid valve device for controlling openings provided in a tubular portion of a valve housing by displacing a valve member in the tubular portion using a driving force provided by an electromagnetic driving mechanism.
2. Description of Related Art
In JP-A-7-293729, the following solenoid valve device is disclosed. In the solenoid valve device, a spool as a valve member is disposed in a valve housing formed in a circular tube shape in a state where the spool can reciprocate in the valve housing. The spool is displaced by a driving force generated at an electromagnetic driving portion, thereby controlling a communication state among openings provided on a peripheral wall of the valve housing.
In the conventional solenoid valve device disclosed in JP-A-7-293729, as shown in FIG. 11, an outer diameter of an electromagnetic driving portion 101 of a solenoid valve device 100 is larger than an outer diameter of a valve housing 110. When this solenoid valve device 100 is used as a hydraulic control valve for controlling the oil pressure of an oil supplied to a hydraulic control apparatus of an automatic gear of a vehicle, the electromagnetic driving portion 101 protrudes from a body 120 of the hydraulic control apparatus. Since it is feared that the electromagnetic driving portion 101 may interfere with components around the body 120, it is desired to mount the solenoid valve device 100 in the body 120. Although the solenoid valve device 100 is prevented from interfering with other components by changing a mounting direction of the solenoid valve device 100, it is feared that the body 120, in which the solenoid valve device 100 is disposed, is required to be thick to accommodate the mounting direction of the solenoid valve device 100. If a step-shaped hole is provided in the body 120, the entire solenoid valve device 100 can be disposed within the body 120. However, this increases the number of manufacturing processes to be performed on the body 120.
The electromagnetic driving portion 101 is connected to the valve housing 110 by crimping a flange provided on the valve housing at a side of the electromagnetic driving portion 101. Since the outer diameter of the flange is larger than the outer diameter of the tube portion of the valve housing 110, when the valve housing 120 is formed by cutting, it is required to begin with a base material considerably larger in diameter than the outer diameter of the tube portion, thereby increasing the amount of material to be removed.
Therefore, in order to produce a device that does not physically interfere with other components, it has been proposed to reduce the overall diameter of such a device to eliminate the solenoid valve device 100 on the outside of the body 120, such as the solenoid valve device 100 shown in FIG. 11, or reduce the outside diameter of the electromagnetic driving portion 101 in order to incorporate the electromagnetic driving portion 101 within the valve housing 110.
Thus, it is a first object of the present invention to provide a solenoid valve that can be readily mounted without interfering with other components and a method of manufacturing the solenoid valve. A second object of the present invention is to provide a solenoid valve device which can be readily machined and its manufacturing machining method.
To achieve the objective of the present invention, there is provided a solenoid valve device with an electromagnetic driving portion having an outside diameter substantially equal to or smaller than an outside diameter of a tubular portion of a valve housing. Since the entire solenoid valve device can be disposed within a cylindrical reception hole, the solenoid valve device can be prevented from interfering with other components. Additionally, the number of machining steps to produce the reception hole can be reduced.
The outer diameter of the electromagnetic driving portion can be slightly larger than the outer diameter of the tubular portion of the valve housing as long as any contained fluid is prevented from leaking through the clearance between the valve housing and an inner wall defining the cylindrical reception hole when the solenoid valve device is disposed within the cylindrical reception hole. An outer diameter of the flange of the valve housing is equal to or smaller than an outer diameter of the tube portion of the valve housing. Accordingly, the amount of material to be removed is decreased when the valve housing is formed by cutting a base material of reduced diameter when the electromagnetic driving portion is made no larger than the diameter of the valve housing. Further, the valve housing can be machined by through-feed cutting, thereby decreasing the cutting time of the valve housing.
In a method of producing the solenoid valve according to the present invention, the valve housing includes an annular recess portion on its peripheral wall. Accordingly, when a crimping tool approaches the yoke, located at a periphery of the flange, to crimp the yoke to the flange in a direction perpendicular to a longitudinal direction of the tube portion, the crimping tool protrudes into the annular recess portion without making contact with the valve housing. Additionally, at least one notch is provided on the open end of the yoke around a circumference of the yoke. Accordingly, deformation of the yoke, generated at a time of crimping the open end of the yoke, is absorbed into the notch, thereby preventing the yoke from being deformed. Additionally, at least one recess portion is provided on the circumferential portion of the flange. Further, this deformed portion at the open end of the yoke is entered into the recess portion, thereby preventing the yoke from being rotated relative to the valve housing.